1. Field of the Invention
The present invention relates to image forming apparatus which have an image forming unit removably attached to the body of the apparatus.
2. Description of the Prior Art
Image forming apparatus have already been proposed which comprise an image forming unit including a photosensitive drum, sensitizing charger and the like in addition to a developing device and removably installable in the body of the apparatus, and toner supply means provided in the apparatus body for the developing device and having a toner supply opening. With the image forming unit installed in the apparatus body, the toner supply opening is positioned above, and opposed to, a toner receiving opening of the developing device in communication therewith. The toner supply opening is opened or closed by moving a cover member in operative relation with the installation or removal of the image forming unit.
However, the proposed image forming apparatus has the problem that if the image forming unit is removed quickly, the toner supply opening moves away from the receiving opening before the supply opening is completely closed with the cover member, permitting some toner to fall from the supply opening to spill over the neighborhood to cause staining.